Heat insulating storage, voyage data recording unit and voyage data recording apparatus

ABSTRACT

This disclosure provides a heat insulating storage, which includes a first heat insulating member arranged outside an accommodating space and having a heat contraction property and a second heat insulating member for protecting the first heat insulating member from a heat and having a heat expansion property.

CROSS-REFERENCE TO RELATED APPLICATION(S)

The application claims priority under 35 U.S.C. §119 to Japanese PatentApplication No. 2010-194693, which was filed on Aug. 31, 2010, theentire disclosure of which is hereby incorporated by reference.

TECHNICAL FIELD

The present invention generally relates to a heat insulating storage.

BACKGROUND

Conventionally, heat insulating storages (storages) for protectingcontents having low heat resistance, such as paper sheets, films, andelectronic instruments, from heat, such as a fire, are known.JP08-214932A discloses such a kind of storage.

JP08-214932A discloses a fire-resistant storage constituted with aprimary storage made of a wall member impregnated with nonflammableliquid, and a secondary storage made of a heat insulating member.Further, in the configuration of JP08-214932A, between the primarystorage and the secondary storage, a member having a heat insulatingproperty and moisture resistance is arranged. By this configuration, thefire-resistant storage has the fire resistance, the heat insulatingproperty, and the moisture resistance, and can effectively protect thecontents from heat.

In JP08-214932A, particular examples of the material used for theprimary storage include a configuration in which a water absorbable fireresistant plate such as a calcium silicate plate is sandwiched betweensteel plates. Further, particular examples of the material for thesecondary storage include a paulownia particle board, fluorine resin,and silicon resin. Furthermore, particular examples of the materialarranged between the primary and secondary storages include fiberglass,cork, and silicon resin.

However, with the member disclosed in JP08-214932A, the wall memberneeds to be thick in order to sufficiently protect the contents under asevere temperature condition. In this case, an internal capacity becomessmaller with respect to external dimensions of the fire-resistantstorage.

Mean while, as a kind of such a heat insulating member, a heatinsulating member having a porous (microporous) structure is known. Thisporous heat insulating member is known that its heat insulatingperformance is high but in a high temperature state (around 1,000° C.depending on the kind of the member and its surrounding condition), itcontracts. When such a contraction occurs, a gap is generated at, forexample, a joint part of the porous heat insulating member and, thereby,the heat insulating performance degrades. Therefore, a function that canbe implemented in the high temperature state and has an increasedinternal capacity with respect to the outline dimension of thefire-resistant storage cannot be provided only by simply using thisporous heat insulating member for the configuration of the memberdisclosed in JP08-214932A.

SUMMARY

The present invention is made in view of the above situations andprovides a heat insulating storage that can endure a high temperatureand has a configuration in which an internal capacity thereof withrespect to an outline dimension is large.

According to an aspect of the invention, a heat insulating storage witha configuration below is provided. That is, the heat insulating storageincludes a first heat insulating member arranged outside anaccommodating space and having a heat contraction property, and a secondheat insulating member for protecting the first heat insulating memberfrom a heat and having a heat expansion property.

Thereby, the second heat insulating member expands before or after theheat is conducted to the first heat insulating member to cause thecontraction, and therefore, a gap that is generated by the contractionof the first heat insulating member can be filled. Thus, a degradationof a heat insulating performance of the first heat insulating member inthe high temperature state can be prevented. Moreover, the heatinsulating performance can be maintained without increasing a thicknessof the first heat insulating member and, therefore, the heat insulatingstorage with a compact structure can be achieved.

The heat insulating storage may further include an accommodatingcontainer formed with the accommodating space therein.

Thereby, accommodated contents can mechanically be protected by theaccommodating container. Moreover, by using an accommodating containeradaptive to a characteristic of the accommodated contents, the contentscan be protected even from other than the heat. For example, if theaccommodated contents are weak in water, by using a container havingmoisture resistance and water resistance, the accommodated contents canbe protected also from water.

A temperature of the second heat insulating member when it starts toexpand may be below or substantially the same as a temperature of thefirst heat insulating member when it starts to contract.

Thereby, the second heat insulating member expands prior to, or atsubstantially the same time as, the beginning of the contraction of thefirst heat insulating member. Thus, the gap generated due to thecontraction of the first heat insulating member does not become largeand the heat insulating performance can be maintained.

The second heat insulating member may have a heat resistant property inaddition to the heat insulating property.

Thereby, even if a fire occurs, the second heat insulating memberexpands without burning. Thus, the degradation of the heat insulatingperformance of the first heat insulating member can be prevented.

The first heat insulating member may include a plurality of first heatinsulating sub members.

That is, in a case where the first heat insulating sub members arestacked on top of another, when the first heat insulating memberincluding the plurality of first heat insulating sub members contractsin the high temperature state, a gap is generated at a part joining thefirst heat insulating sub members and, thereby, the heat insulatingperformance significantly degrades. However, according to the aspects ofthe present invention, the gap can be filled by the second heatinsulating member and the degradation of the heat insulating performancecan be prevented. Moreover, because the first heat insulating memberincludes the plurality of first heat insulating sub members, a shape ofthe first heat insulating member can easily be changed by, for example,adjusting the number of the first heat insulating sub members. Thereby,the first heat insulating member can flexibly correspond to a change ofdesigns of the heat insulating storage.

One or more of the first heat insulating sub members may be arranged tobe adjacent on the outside to the rest of the one or more first heatinsulating sub members.

Thereby, even in the case where the first heat insulating sub memberarranged on the outside contracts and the gap is generated, by the firstheat insulating sub member on the other side, an influence of the gapcan be reduced. Therefore, the degradation of the heat insulatingperformance of the first heat insulating member in the high temperaturestate can effectively be prevented.

The second heat insulating member may be arranged outside the first heatinsulating member.

Thereby, the accommodated contents can effectively be protected from theheat from outside.

A hollow space may be formed in the first heat insulating sub member andat least a part of the hollow space serves as the accommodating space.

Thereby, when a heat is conducted to the one or more first heatinsulating sub members on the outside and the contraction thereof iscaused, the one or more first heat insulating sub members on the innerside is constricted. Therefore, because a stress is caused in the one ormore first heat insulating sub members on the inner side, the gap isdifficult to be generated even if the inner side is in the hightemperature state. Therefore, the degradation of the heat insulatingperformance of the first heat insulating member in the high temperaturestate can effectively be prevented so that the accommodated contents canfurther surely be protected from the heat.

In the first heat insulating member, the first heat insulating submembers may be stacked on top of another, and one or more parts joiningthe adjacently stacked first heat insulating sub members on the outsidedo not overlap with one or more parts joining the adjacently stackedfirst heat insulating sub members on the inner side.

Thus, in the high temperature state, end parts (i.e., joint parts) ofthe first heat insulating sub members contract, and the heat insulatingperformance degrades. In this regard, according to the aboveconfiguration, the parts of the inner heat insulating sub member andouter heat insulating sub member where the heat insulating performancedegrades do not overlap with each other. Therefore, the degradation ofthe heat insulating performance of the entire heat insulating storagecan effectively be prevented.

According to another aspect of the invention, a voyage data (i.e.,navigation data) recording unit with a configuration below is provided.That is, the voyage data recording unit includes the heat insulatingstorage of any of the other aspects and a storing device for storingvoyage data, the storing device being accommodated within theaccommodating space.

That is, the storing device is commonly configured so as to be weak inheat, therefore, the storing device needs to robustly be protected fromthe heat such as the fire. Moreover, because an arranging space in theship is limited, the voyage data recording unit is desired to have acompact structure. Therefore, by applying the aspects of the presentinvention to the voyage data recording unit, the effects that achievethe compact structure while maintaining the heat insulating performancecan further effectively be provided.

According to another aspect of the invention, a voyage data recordingapparatus with a configuration below is provided. That is, the voyagedata recording apparatus includes the voyage data recording unit of theother aspect and a voyage data collecting unit for receiving voyage datafrom a ship instrument and transmitting the voyage data to the voyagedata recording unit.

Thereby, the voyage data recording apparatus that can robustly protectthe voyage data can be provided.

According to another aspect of the invention, a heat insulating storagewith a configuration below is provided. That is, the heat insulatingstorage includes a first heat insulating member having a heatcontraction property and a second heat insulating member arranged at aposition that is outside an accommodating space and on an inner side ofthe first heat insulating member, and having a heat expansion property.

Thereby, the second heat insulating member expands before or after theheat is conducted to the first heat insulating member to cause thecontraction, and therefore, the gap generated by the contraction of thefirst heat insulating member can be filled. Thus, the degradation of theheat insulating performance of the first heat insulating member in thehigh temperature state can be prevented. Therefore, a circumference ofthe heat insulating storage can effectively be protected from a heatgenerated inside the heat insulating storage.

A temperature of the second heat insulating member when it starts toexpand may be below or substantially the same as a temperature of thefirst heat insulating member when it starts to contract.

Thereby, the second heat insulating member expands prior to, or atsubstantially the same time as, the beginning of the contraction of thefirst heat insulating member. Thus, the gap generated due to thecontraction of the first heat insulating member does not become largeand the heat insulating performance can be maintained.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure is illustrated by way of example and not by wayof limitation in the figures of the accompanying drawings, in which thelike reference numeral indicate like elements and in which:

FIG. 1 is a block diagram showing a configuration of a voyage datarecording apparatus according to an embodiment of the present invention;

FIG. 2 is an external perspective view of a data recording unit;

FIG. 3 is an front cross-sectional view showing a configuration ofinside the data recording unit;

FIG. 4 is a perspective view showing a porous heat insulating member;

FIGS. 5A to 5D are views schematically explaining how the porous heatinsulating member contracts due to a temperature increase;

FIG. 6 is a front cross-sectional view showing inside an outer capsuleafter the temperature increase;

FIG. 7 is a cross-sectional view in which a boundary part of an outerheat insulating member and a sheet-type heat insulating member isenlarged;

FIG. 8 is a chart comparing a case where the heat is insulated only bythe porous heat insulating member and a case where the heat is insulatedby the porous heat insulating member and the sheet-type heat insulatingmember;

FIG. 9 is a front cross-sectional view schematically showing aconfiguration of a container for heat insulation according to anotherembodiment of the present invention; and

FIGS. 10A to 10C are enlarged cross-sectional views showing geometriesof a joined part of sub members of the inner or outer heat insulatingmember.

DESCRIPTION OF EMBODIMENTS

Next, embodiments of the present invention are described with referenceto the appended drawings. FIG. 1 is a block diagram showing aconfiguration of a voyage data recording apparatus 10 of thisembodiment.

The voyage data recording apparatus 10 can record data relating to anoperation of a ship that is equipped with the apparatus 10 (hereinafter,referred to as “the ship concerned” or may be simply referred to as “theship”) and various kinds of matters that occur in the ship. If a marineaccident occurs, the recorded data is analyzed to be used fordetermining the cause and preventing a reoccurrence of the accident.

As shown in FIG. 1, the voyage data recording apparatus 10 includes adata collecting unit 11 (voyage data collecting unit) and a datarecording unit 12 (heat insulating storage or voyage data recordingunit).

The data collecting unit 11 is electrically connected with shipinstrument 13 and is inputted with various data relating to voyage(voyage data) from the ship instrument 13. Particular examples of theship instrument 13 include a GPS device for measuring a position of theship and date and time, a speed sensor for measuring a speed of theship, various compasses for measuring a bow azimuth direction, a vaneanemometer for detecting a direction and speed of wind on the sea wherethe ship travels, a depth finder for measuring a water depth, amicrophone for receiving sounds from a bridge, and a radar device foracquiring a radar image indicating situations around the ship.

The data collecting unit 11 mainly includes an input-output module 21for loading the voyage data, a signal processing module 22 forprocessing the loaded voyage data. This collected voyage data istransmitted from the input-output module 21 to a data converting device36 of the data recording unit 12.

The data converting device 36 converts the received voyage data into adata format suitable for storage and transmission, and outputs theconverted data to a memory board 64 (storing device). This memory board64 includes a memory as a storage element and a circuit board on whichthe memory is mounted.

The memory can store a predetermined time length (e.g., 13 hours) worthof the voyage data, and data older than the predetermined time length isoverwritten with the latest data as needed. When it is determined that,for example, a marine accident has occurred, the overwriting of the datais stopped and the memory continues to hold the voyage data immediatelybefore the marine accident. Note that, this memory is protected so as towithstand a fire and water (submersion) caused by a marine accident,therefore the voyage data can be collected and analyzed even after theaccident.

Next, a configuration of the data recording unit 12 is described indetail with reference to FIGS. 2 to 4. FIG. 2 is an external perspectiveview of the data recording unit 12. FIG. 3 is a front cross-sectionalview showing a configuration of inside the data recording unit 12. FIG.4 is a perspective view showing a configuration of a porous heatinsulating member 51.

As shown in FIG. 2, the data recording unit 12 is constituted with abase 34, a beacon 32, and an outer capsule 30.

The base 34 is to fix the outer capsule 30 to the ship and is connectedto a lower part of the outer capsule 30. The base 34 is formed in arectangular shape and attaching holes 35 are formed in four corner partsthereof. By using suitable attachment hardwares for the attaching holes35, the outer capsule 30 can be fixed to the ship.

The beacon 32 is attached to a side surface part of the outer capsule 30and can emit acoustic waves. When the data recording unit 12 is missingafter the marine accident, it can be found by following the acousticwaves.

The outer capsule 30 is equipped with the main components of the datarecording unit 12 inside thereof, and it is particularly for protectingthe memory. The outer capsule 30 is formed substantially in a cylindershape, and a round-shaped cable 31 for receiving the voyage data fromthe data collecting unit 11 is attached to the side surface of thecapsule 30. The data recording unit 12 receives, via the round-shapedcable 31 connected with the outer capsule 30, the voyage datatransmitted from the data collecting unit 11.

As shown in FIG. 3, the round-shaped cable 31 is connected with the dataconverting device 36. The data converting device 36 is arranged in anupper part of the inside the outer capsule 30. As above, because thedata converting device 36 is arranged outside a heat insulating member(later described in detail) for protecting the memory from the heat, anincrease in temperature near the memory due to an operation heat of thedata converting device 36 can be prevented. Further, the data convertedby the data converting device 36 is outputted to a central part of theouter capsule 30 through a transmission cable 40.

An inner capsule 44 (accommodating container), a holding capsule 45, aporous heat insulating member (first heat insulating member) 51, andsheet-type heat insulating members 52 (second heat insulating members)are arranged in the central part of the outer capsule 30 in this orderfrom the inner side.

The inner capsule 44 is a container made of a thick metallic materialand a lid part and a body part thereof are fixed together by bolts inthis embodiment. A connector device 65 is arranged on an outer surfaceof the lid part and is electrically connected with the data convertingdevice 36 by the transmission cable 40. Further, the connector device 65is connected, through a cable not illustrated, with the memory board 64arranged inside the inner capsule 44 (accommodating space). With thisconfiguration, the voyage data can be stored in the memory of the memoryboard 64.

Further, the inner capsule 44 is configured as a waterproof container,thereby, water does not enter into the inner capsule 44 from between thelid part and the body part thereof or between the connector device 65and the memory board 64. Therefore, even in a case where it is submergedinto the water because of a marine accident, the memory board 64 can beprotected from water.

The holding capsule 45 is arranged outside the inner capsule 44. Aholding member made of a heat insulating member such as rubber isarranged between the inner capsule 44 and the holding capsule 45. Thisholding member supports the inner capsule 44 to the holding capsule 45so that it floats and a heat in the holding capsule 45 is not conductedto the inner capsule 44. The porous heat insulating member 51 isarranged outside the holding capsule 45.

The porous heat insulating member 51 is a heat insulating member havinga structure in which a plurality of very small holes (microholes) areformed. The porous heat insulating member 51, in spite of having a highheat insulating performance, contracts when reaching a certaintemperature or above (contraction staring temperature). The percentageof contraction differs depending on a kind of the member and itssurrounding condition, for example, in a case where the porous heatinsulating member is left for 500 hours at a temperature of about 1,000°C., the percentage of contraction is approximately 10%. Further, asshown in FIGS. 3 and 4, the porous heat insulating member 51 isconstructed as a heat insulating member having a two-layer structureincluding an inner heat insulating member 71 (first heat insulating submember) arranged to be in contact with an outer circumferential surfaceof the holding capsule 45 and an outer heat insulating member 72 (firstheat insulating sub member) arranged to be in contact with an outercircumferential surface of the inner heat insulating member 71.

Note that, the first heat insulating sub member indicates the heatinsulating members constructing the porous heat insulating member 51,and in addition to the inner heat insulating member 71 and the outerheat insulating member 72, each member constructing the inner heatinsulating member 71 and each member constructing the outer heatinsulating member 72 may be referred to as the first heat insulating submember.

As shown in FIG. 4, the inner heat insulating member 71 is constructedwith annular members (ring-shaped members) vertically aligned, acircular plate member arranged on an inner side of the uppermost annularmember, and a circular plate member arranged on the inner side of thelowermost annular member.

The outer heat insulating member 72 is constructed with annular members(ring-shaped members) vertically aligned, a circular plate memberarranged on an inner side of the uppermost annular member, and acircular plate member arranged on the inner side of the lowermost theannular member. As above, the inner heat insulating member 71 and theouter heat insulating member 72 are formed in a hollow cylinder shapeand the inner capsule 44 and the holding capsule 45 are arranged withinthis hollow space (on the inner side of the inner heat insulating member71).

The porous heat insulating member 51 is configured as above, and thesheet-type heat insulating members 52 are arranged outside the outerheat insulating member 72.

The sheet-type heat insulating member 52 is a sheet-type heat resistantheat insulating member arranged to cover an external surface of theouter heat insulating member 72. In this embodiment, a singlerectangular sheet-type heat insulating heat insulating member 52 coversthe side surface of the outer heat insulating member 72 and two circularsheet-type heat insulating members 52 cover the upper part and the lowerpart of the outer heat insulating member 72, respectively.

The sheet-type heat insulating member 52 is made of organic members,such as thermoplastic resin, rubber, and epoxy resin, and an inorganicfiller containing layered inorganic substances such as neutralized blacklead. With this composition, the sheet-type heat insulating member 52has heat resistance and heat insulating performance, and expands at apredetermined temperature (expansion starting temperature) or above. Thepercentage of expansion differs depending on a kind of the member andits surrounding condition, for example, it may be several times todozens of times (three to fifty times) the case with a temperature belowthe predetermined temperature. Further, the percentage of expansion anda direction of the expansion can suitably be adjusted by, for example, acombination of the members and an arrangement of the layered inorganicsubstances and, in this embodiment, the sheet-type heat insulatingmember 52 expands in its thickness direction.

Note that, as long as the sheet-type heat insulating member 52 has theheat insulating property and the property to expand in the hightemperature state, the configuration thereof is not limited to the aboveand suitable substances may be used.

Next, behaviors that are seen in the porous heat insulating member 51and the sheet-type heat insulating member 52 when the data recordingunit 12 of this embodiment is heated are described with reference to theFIGS. 5 to 8. FIGS. 5A to 5D are views schematically explaining how theporous heat insulating member 51 contracts due to a temperatureincrease. FIG. 6 is a front cross-sectional view showing inside theouter capsule 30 after the temperature increase. FIG. 7 is across-sectional view in which a boundary area of the outer heatinsulating member 72 and the sheet-type heat insulating member 52 isenlarged. FIG. 8 is a chart comparing the heat insulating performancebetween a case where the heat is insulated only by the porous heatinsulating member 51 and a case where the heat is insulated by theporous heat insulating member 51 and the sheet-type heat insulatingmember 52.

First, the behavior that is seen in the porous heat insulating member 51when the sheet-type heat insulating member 52 is not used and only theporous heat insulating member 51 is heated is explained. FIGS. 5A and 5Bshow a cross-sectional view and a perspective view of the porous heatinsulating member 51 before being heated, respectively.

Then, if a fire occurs, when the porous heat insulating member 51 isheated and the outer heat insulating member 72 reaches the contractionstarting temperature or above, the porous heat insulating member 51deforms to have shapes as shown in FIGS. 5C and 5D. Note that, the FIGS.5C and 5D show a cross-sectional view and a perspective view of theporous heat insulating member 51 after being heated, respectively.

When the fire occurs, because the fire and the heat are conducted fromthe outside, the outer circumferential part of the outer heat insulatingmember 72 is heated the most in the porous heat insulating member 51, asshown in FIGS. 5C and 5D. Therefore, the outer circumferential part ofthe outer heat insulating member 72 contracts the most. Note that,although a contraction amount of the side surface of the outer heatinsulating member 72 is uniform in FIGS. 5A to 5D, actually, adifference may be caused in the contraction level depending on aposition of the side surface due to, for example, how the heat conductsat the time of the fire.

When the contraction is caused in the porous heat insulating member 51as above, a gap is generated in a part (joint) joining the adjacent submembers. Further, this gap becomes an entry route for the heat andthereby, at this gap, the function as the heat insulating member cannotsubstantially be provided. Therefore, when the outer heat insulatingmember 72 and the inner heat insulating member 71 of which the heatinsulating property is decreased fail to insulate the heat from theoutside (e.g., the outside of the porous heat insulating member 51), atemperature inside the inner capsule 44 reaches a maximum resistibletemperature of the memory or above, and causes a breakage of the memory.

Note that, although, depending on a heating time length and a heatingtemperature, the gap may be generated in the inner heat insulatingmember 71, in this embodiment, the gap is difficult to be generated inthe inner heat insulating member 71 for a following reason. That is,within the sub members of the outer heat insulating member 72, theannularly formed member (hereinafter, referred to as the outer annularmember) is reduced in its inner diameter when the contraction is caused.Therefore, the contracted outer annular member tightly constricts theinner heat insulating member 71. Thus, the sub member of the inner heatinsulating member 71 is difficult to contract and the gap is difficultto be generated.

Note that, if a porous heat insulating member having a single-layerstructure (structure in which the inner heat insulating member 71 is notarranged) is applied in this embodiment, a heat from the outsidedirectly conducts inside the porous heat insulating member from the gapand, thereby, a temperature of the inner capsule 44 immediatelyincreases and the memory becomes easy to break. In this regard, theporous heat insulating member 51 of this embodiment has the two-layerstructure, therefore, even in the case where the outer heat insulatingmember 72 is contracted, the heat from the outside is insulated by theinner heat insulating member 71 and is not directly conducted inside theporous heat insulating member 51 from the gap in the outer heatinsulating member 72. Therefore, the porous heat insulating member 51 ofthis embodiment has higher heat insulating performance compared to theheat insulating member having the single-layer structure with the samethickness as the total thickness of the inner heat insulating member 71and the outer heat insulating member 72.

Next, behaviors that are seen in the porous heat insulating member 51and the sheet-type heat insulating member 52 when the porous heatinsulating member 51 covered by the sheet-type heat insulating member 52is heated is explained. When a fire occurs, the sheet-type heatinsulating member 52 arranged on the outer side is first heated. Thesheet-type heat insulating member 52, when being heated and reaching theexpansion starting temperature or above, expands in its thicknessdirection. Moreover, the porous heat insulating member 51, when reachingthe contraction starting temperature, starts to contract.

Note that, in this embodiment, the heat insulating performance and thethickness of the sheet-type heat insulating member 52 is determined sothat the outer heat insulating member 72 reaches near the contractionstarting temperature when the sheet-type heat insulating member 52reaches near the expansion starting temperature.

Therefore, before or after the outer heat insulating member 72 contractsand generate the gap, as shown in FIGS. 6 and 7, the sheet-type heatinsulating member 52 expands to fill the gap. Thus, the part of theouter heat insulating member 72 where the heat insulating performancehas degraded due to the gap can be compensated by the sheet-type heatinsulating member 52 by filling the gap as above, therefore, the heatinsulating performance can be maintained.

Note that, here, if the sheet-type heat insulating member 52 expandswith a certain time length (a delay) after the outer heat insulatingmember 72 contracts and the gap is generated, the size of the gap maybecome large before the sheet-type heat insulating member 52 expands,and the heat insulating performance may degrade. Therefore, theexpansion starting temperature of the sheet-type heat insulating member52 and the contraction starting temperature of the outer heat insulatingmember 72 are preferred to be determined so that the expansion startingtemperature of the sheet-type heat insulating member 52 is lower than orsubstantially the same as the contraction starting temperature of theouter heat insulating member 72. That is, by having the sheet-type heatinsulating member 52 expand prior to, or at substantially the same timeas, the beginning of the contraction of the outer heat insulating member72, the gap generated due to the contraction of the outer heatinsulating member 72 does not become large and therefore the heatinsulating performance can be maintained.

FIG. 8 shows a chronological change of the temperature inside the innercapsule 44 when the heat is insulated only by the porous heat insulatingmember 51, and, as in this embodiment, a chronological change of thetemperature inside the inner capsule 44 when the heat is insulated byboth of the porous heat insulating member 51 and the sheet-type heatinsulating member 52. As shown in FIG. 8, when the heat is insulatedonly by the porous heat insulating member 51, the heat insulatingproperty cannot be secured due to the contraction of the porous heatinsulating member 51 and, therefore, the temperature increase cannot besuppressed and the temperature inside the inner capsule 44 becomes high.In this regard, with the configuration of this embodiment, the heatinsulating performance can be maintained by the expansion of thesheet-type heat insulating member 52 even if the porous heat insulatingmember 51 contracts, therefore, as shown in FIG. 8, the temperatureincrease inside the inner capsule 44 can be suppressed.

As described above, the data recording unit 12 includes the porous heatinsulating member 51 and the sheet-type heat insulating member 52. Theporous heat insulating member 51 is arranged outside the accommodatingspace. The sheet-type heat insulating member 52 is arranged so as toprotect the porous heat insulating member 51 from the heat.

Thereby, the sheet-type heat insulating member 52 expands before orafter the heat conducts to the porous heat insulating member 51 to causethe contraction, and therefore, the gap generated by the contraction ofthe porous heat insulating member 51 can be filled. Thus, thedegradation of the heat insulating performance of the porous heatinsulating member 51 in the high temperature state can be prevented.Moreover, the heat insulating performance can be maintained withoutincreasing the thickness of the porous heat insulating member 51 and,therefore, the data recording unit 12 with a compact structure can beachieved.

Further, the data recording unit 12 of this embodiment includes theinner capsule 44 formed with the accommodating space therein.

Thereby, the memory can be mechanically protected by the inner capsule44. Moreover, because the inner capsule 44 has a waterproof structure,it can protect the memory even if it is submerged into the water.

Further, in the data recording unit 12 of this embodiment, thesheet-type heat insulating member 52 is arranged outside the porous heatinsulating member 51.

Thereby, the memory can effectively be protected from a heat fromoutside the porous heat insulating member 51, such as a fire.

Further, in the data recording unit 12 of this embodiment, thesheet-type heat insulating member 52 has a heat resistant property inaddition to a heat insulating property.

Thereby, even if the fire occurs, the sheet-type heat insulating member52 expands without burning. Thus, the degradation of the heat insulatingperformance of the porous heat insulating member 51 can be prevented.

Further, in the data recording unit 12 of this embodiment, the porousheat insulating member 51 is constructed with the plurality of firstheat insulating members.

Thereby, the gaps generated among the plurality of first heat insulatingsub members can be filled by the sheet-type heat insulating member 52.Therefore, the degradation of the heat insulating performance of thefirst heat insulating sub members can be prevented. Moreover, becausethe porous heat insulating member 51 is constructed with the pluralityof first heat insulating sub members, the shape of the porous heatinsulating member 51 can easily be changed by adjusting the number ofthe first heat insulating sub members. Thus, the porous heat insulatingmember 51 can flexibly correspond to a change of shapes of the innercapsule 44 and the holding capsule 45.

Further, in the data recording unit 12 of this embodiment, the porousheat insulating member 51 has the two-layer structure constructed withthe inner heat insulating member 71 and the outer heat insulating member72.

Thereby, even in the case where the outer heat insulating member 72contracts and the gap is generated, the inner heat insulating member 71is arranged on the inner side of the gap. Therefore, the degradation ofthe heat insulating performance of the porous heat insulating member 51in the high temperature state can be prevented.

Further, in the data recording unit 12 of this embodiment, thesheet-type heat insulating member 52 is arranged outside the porous heatinsulating member 51. The first heat insulating sub member includes theannularly-shaped member, and the inner capsule 44 is arranged in theinternal space of this annular member.

Thereby, when a heat conducts to the outer heat insulating member 72 andthe contraction thereof is caused, the inner heat insulating member 71is constricted by the sheet-style insulating member 52. Therefore, thegap is difficult to be generated even if the inner side of the outercapsule 30 is in the high temperature state. Therefore, the degradationof the heat insulating performance of the porous heat insulating member51 in the high temperature state can be prevented.

Further, in the data recording unit 12 of this embodiment, the partsjoining the sub members of the inner heat insulating member 71 arearranged so as not to overlap with the parts joining the sub members ofthe outer heat insulating member 72 which is adjacently arranged outsideof the inner heat insulating member 71.

Thereby, the parts of the inner heat insulating member 71 and the outerheat insulating member 72 where the heat insulating performance degradedo not overlap with each other. Therefore, the degradation of the heatinsulating performance of the entire data recording unit 12 caneffectively be prevented.

The voyage data recording apparatus 10 includes the data recording unit12 and the data collecting unit 11. The data collecting unit 11 receivesthe voyage data and transmits it to the data recording unit 12.

Thereby, the voyage data can robustly be protected.

Next, another embodiment of the present invention is described withreference to FIG. 9. Note that, the configuration same as or similar tothe above embodiment may be applied with the same numeral and thedescription thereof may be omitted.

A heat insulating storage 12 a is not configured as a heat insulatingstorage for protecting contents from a heat and is configured to preventa heat caused by the contents (e.g., a heat due to an operation heat andabnormal ignition) from being conducted outside of the heat insulatingstorage 12 a. This kind of heat insulating storage is used for, forexample, a case of a fuel cell.

The heat insulating storage 12 a includes an accommodating container 44a, a sheet-type heat insulating member 52, and a porous heat insulatingmember 51.

The accommodating container 44 a is a container for accommodating thecontents. Note that, the accommodating container 44 a may be made ofcalcium silicate and gypsum.

The porous heat insulating member 51 and the sheet-type heat insulatingmember 52 have the similar properties as in the above embodiment,respectively, and are arranged in different positions. That is, in theabove embodiment, the outer side of the porous heat insulating member 51is covered by the sheet-type heat insulating member 52; however, in thisembodiment the inner side of the porous heat insulating member 51 iscovered by the sheet-type heat insulating member 52.

With this configuration, even if a high temperature heat or a fire iscaused by the contents within the accommodating container 44 a, by thesimilar function as the above embodiment, the heat can be prevented frombeing conducted outside.

The preferred embodiments of the present invention are described above;however, the above configurations may be modified as follows, forexample.

The shapes of the inner capsule 44 and the accommodating container 44 aare not limited to the above examples and may suitably be modified.Alternatively, the hollow space inside the porous heat insulating member51 may be used as an accommodating space and the accommodating containersuch as the inner capsule 44 may be omitted in the configuration.

The shape of the porous heat insulating member 51 is not limited to thehollow cylinder shape and may suitably be changed, for example, to be ahollow cuboid. Further, the porous heat insulating member 51 may have asingle-layer structure or a multiple-layer structure such as athree-layer structure, instead of the two-layer structure.Alternatively, the number of layers of the porous heat insulating member51 may be varied depending on position, for example, most parts of theporous heat insulating member 51 may be structured in a single-layer andthe rest of the parts thereof may be structured in two-layers. As above,various kinds of shapes may be considered for the porous heat insulatingmember 51, and any of the shapes can provide effects according to theembodiments of the present invention.

Further, alternative to using the porous heat insulating member 51 thatis constructed by the separate heat insulating members, a porous heatinsulating member 51 that is integrally constructed may be used. In thiscase, the porous heat insulating member 51 contracts due to atemperature increase and a space is generated between the porous heatinsulating member 51 and the sheet-type heat insulating member 52. Thenthe sheet-type heat insulating member 52 expands to fill the space,therefore, the degradation of heat insulating performance can beprevented.

In the inner heat insulating member 71 and the outer heat insulatingmember 72 of the above embodiments, joined parts of annular members thatare stacked on top of another are formed in a linear shape (see FIGS. 3and 10A); however, alternative to this configuration, either one ofconcave and convex parts may be formed at both end parts of the annularmember so that the joined part of the stacked annular member may benon-linear (see FIGS. 10B and 10C). In this case, a length of the joinedpart becomes longer and, thereby, the degradation of the heat insulatingperformance due to the heat contraction can be suppressed.

In the above embodiments, the heat insulating member formed into a sheetis used as the second heat insulating member; however, a thick heatinsulating member may be used as the second heat insulating member.

In the above embodiments, the example where the heat insulating memberis applied to the data recording unit is described; however, it may beapplied to, for example, a heat resistant vault and a case foraccommodating a thermometer for a blast furnace.

In the foregoing specification, specific embodiments of the presentinvention have been described. However, one of ordinary skill in thetechnique appreciates that various modifications and changes can beperformed without departing from the scope of the present invention asset forth in the claims below. Accordingly, the specification andfigures are to be regarded in an illustrative rather than a restrictivesense, and all such modifications are intended to be included within thescope of present invention. The benefits, advantages, solutions toproblems, and any element(s) that may cause any benefit, advantage, orsolution to occur or become more pronounced are not to be construed as acritical, required, or essential features or elements of any or all theclaims. The invention is defined solely by the appended claims includingany amendments made during the pendency of this application and allequivalents of those claims as issued.

Moreover in this document, relational terms such as first and second,top and bottom, and the like may be used solely to distinguish oneentity or action from another entity or action without necessarilyrequiring or implying any actual such relationship or order between suchentities or actions. The terms “comprises,” “comprising,” “has,”“having,” “includes,” “including,” “contains,” “containing” or any othervariation thereof, are intended to cover a non-exclusive inclusion, suchthat a process, method, article, or apparatus that comprises, has,includes, contains a list of elements does not include only thoseelements but may include other elements not expressly listed or inherentto such process, method, article, or apparatus. An element proceeded by“comprises . . . a,” “has . . . a,” “includes . . . a,” “contains . . .a” does not, without more constraints, preclude the existence ofadditional identical elements in the process, method, article, orapparatus that comprises, has, includes, contains the element. The terms“a” and “an” are defined as one or more unless explicitly statedotherwise herein. The terms “substantially,” “essentially,”“approximately,” “about” or any other version thereof, are defined asbeing close to as understood by one of ordinary skill in the technique,and in one non-limiting embodiment the term is defined to be within 10%,in another embodiment within 5%, in another embodiment within 1% and inanother embodiment within 0.5%. The term “coupled” as used herein isdefined as connected, although not necessarily directly and notnecessarily mechanically. A device or structure that is “configured” ina certain way is configured in at least that way, but may also beconfigured in ways that are not listed.

1. A heat insulating storage, comprising: a first heat insulating memberarranged outside an accommodating space and having a heat contractionproperty; and a second heat insulating member for protecting the firstheat insulating member from a heat and having a heat expansion property.2. The heat insulating storage of claim 1, further comprising anaccommodating container formed with the accommodating space therein. 3.The heat insulating storage of any one of claim 1 or 2, wherein atemperature of the second heat insulating member when it starts toexpand is below or substantially the same as a temperature of the firstheat insulating member when it starts to contract.
 4. The heatinsulating storage of claim 1, wherein the second heat insulating memberhas a heat resistant property in addition to the heat insulatingproperty.
 5. The heat insulating storage of claim 1, wherein the firstheat insulating member includes a plurality of first heat insulating submembers.
 6. The heat insulating storage of claim 5, wherein one or moreof the first heat insulating sub members are arranged to be adjacent onthe outside to the rest of the one or more first heat insulating submembers.
 7. The heat insulating storage of claim 6, wherein the secondheat insulating member is arranged outside the first heat insulatingmember.
 8. The heat insulating storage of claim 7, wherein a hollowspace is formed in the first heat insulating sub member and at least apart of the hollow space serves as the accommodating space.
 9. The heatinsulating storage of claim 7 or 8, wherein in the first heat insulatingmember, the first heat insulating sub members are stacked on top ofanother, and one or more parts joining the adjacently stacked first heatinsulating sub members on the outside do not overlap with one or moreparts joining the adjacently stacked first heat insulating sub memberson the inner side.
 10. A voyage data recording unit, comprising: theheat insulating storage of claim 1; and a storing device for storingvoyage data, the storing device being accommodated within theaccommodating space.
 11. A voyage data recording apparatus, comprising:the voyage data recording unit of claim 10; and a voyage data collectingunit for receiving voyage data from a ship instrument and transmittingthe voyage data to the voyage data recording unit.
 12. A heat insulatingstorage, comprising: a first heat insulating member having a heatcontraction property; and a second heat insulating member arranged at aposition that is outside an accommodating space and on an inner side ofthe first heat insulating member, and having a heat expansion property.13. The heat insulating storage of claim 12, wherein a temperature ofthe second heat insulating member when it starts to expand is below orsubstantially the same as a temperature of the first heat insulatingmember when it starts to contract.